1. Field of the Invention
The present invention relates to a dripless chimney cap employed with or without a stainless steel chimney liner and top plate, in the protection of a chimney from the natural elements of the outside environment and naturally occurring condensation.
2. Discussion of Related Art
A chimney has an opening running its length for conveying exhaust gases from a fireplace, furnace or boiler acting as a heating source. Combustion products in the form of hot exhaust gases rise up the chimney to the outside. They are typically vertical to ensure that the hot gases flow smoothly upward.
The most common fuel sources for modern heating sources include natural gas, liquefied petroleum gas, fuel oil, coal and wood.
All of the above stated combustible sources when burned produce gases and other byproducts such as residue which flow upward within the chimney.
A chimney cap is typically located at the uppermost portion of a chimney to protect the chimney from the external natural elements such as precipitation. It also prevents animals and objects from getting into the chimney. They also act as a spark arrestor.
When the heat, gases and other byproducts flow upward within the chimney, the hot gases cool and create byproducts and residue on the underside of the chimney cap. These condensates drip down onto the top of the chimney and can cause staining, discolorization and corrosion of various materials. These condensates tend to drip out of the chimney cap and onto the outside of the chimney and the roof and walls of the house to which it is attached.
To make this a larger problem, dyes are added to heating oils during their production to differentiate them from diesel oil. These dyes condense out of the exhaust gases. Therefore the condensates can cause considerable staining, discolorization and corrosion.
Some prior art chimney caps are designed to have an open screen section to allow greater exhaust flow. Some of these are designed to allow the condensate to drip into the chimney opening in the absence of cross wind. However, with the pitch of the outer edge of the chimney cap sloping downward, outside the diameter of the chimney opening, the condensate continues to fall on the outside of the chimney opening, with or without a cross wind, causing staining, corrosion and discoloration.
Currently there is a need for a chimney cap system which prevents condensate dripping on the outside of the chimney and the house to which it is attached, so as to prevent staining, discolorization and corrosion of the chimney, even in windy conditions.